The structure of a new maltose phosphate arising from the action of oral bacteria has been elucidated and partially synthesized. A substance present in the bedding of hamsters used in supplying blood to malaria mosquitos has been found to be fatal to the mosquitos. Investigations using solvent partition and GC-MS are underway to determine its nature and the nature of the compound responsible for exflagellation in Anopheles species. A possible novel function for RNA has been found: the polymerization of macrocyclic lactones used by Colletes thoracicus.